1. Field
The present disclosure relates generally to communication, and more specifically signaling uplink transmit power to user equipment (UE) in a wireless communication network.
2. Background
In third generation wireless mobile communication technology, the Universal Mobile Telecommunication System (UMTS), also known as 3GSM (Third Generation Global System for Mobile Communications), is one communication protocol used for communications on a wireless network. One such type of wireless network is a UMTS Terrestrial Radio Access Network (UTRAN) which typically includes base stations and controllers to form the UMTS wireless network. This wireless communications network, commonly referred to as a 3G (for Third Generation) network, can carry many traffic types, from real-time circuit switched traffic to Internet Protocol (IP)-based packet switched traffic. The UTRAN allows connectivity between user equipment (UE), such as mobile phones or wireless communication devices, and to devices on other communication networks.
Base stations typically include transmitters and receivers used to communicate directly with the UE, which may move freely around a network. A Radio Network Controller (RNC) governs communications on the UTRAN by controlling the operation of the base stations on the network. The RNC carries out radio resource management, some of the mobility management functions and is the point where encryption is done before user data is sent to and from Mobile User Equipment (MUE).
Under UTRAN, the RNC can configure UEs operating within the network to operate according to particular communication system parameters. (See 3GPP Technical Specification 25.331) For example, during initiation or reconfiguration, a Radio Bearer Setup message may be sent by the RNC to a UE that configures a transmitter and/or receiver in the UE to operate according to parameters (e.g., combination of transmitted and received data blocks, mapping between channels and services, etc.) sent in the Radio Bearer Setup message. The UE may receive a new Radio Bearer Setup message when it is started or when it awakes from a standby mode. For example, a UE may be configured to conserve power by switching its transmitter and/or receiver On and Off, causing it to have to reset its transmitter and/or receiver parameters.
In some scenarios, a RNC, such as a base station or base node, wishes to use a transmit power that is outside the range that can be signaled in a certain release of the specification. Later releases of the specifications can expand this range, but the older UEs or Mobile Stations (MSs) that are in the field will not understand these new fields. This signaled power is used at the UE mainly for path loss estimation.